As high technologies are developed and advanced, various techniques are being applied to military fields. Especially, development of various sensors and computer hardware enables an unmanned combat system.
Developed countries have been concerned about development of military robots, especially, researches for an unmanned system in the field of national defense is undergoing in the United States in order to dispose unmanned vehicles in a future combat system. Active researches for the unmanned vehicles have been in progress even within the country and development of various unmanned systems is being conducted in the field of national defense.
Examining the course of technical development in the field of the unmanned system, unmanned vehicles may perform various missions, such as reconnaissance and attack, command and control, explosive detection/disposal and the like. Upon employing a wheel drive method in the unmanned vehicle, it is needed to detect (sense) whether or not the wheel contacts a ground in order for the unmanned vehicle to be unaffected by obstacles.
In general, a contact sensor (or pressure sensor) is attached between two objects to check contact or non-contact between the two objects. However, for example, if wheels of the unmanned vehicle occur severe friction at contact portions, the contact sensor may not be easy to be attached thereto.
Therefore, a new type of wheel contact sensing structure to be appropriate for the unmanned vehicle and a method thereof are required.